Experimental Brain Research

, Volume 187, Issue 1, pp 153–160

Redundant target effect and the processing of colour and luminance

Research Article

Abstract

The redundant target effect is the observation that people typically respond faster to double targets (two targets presented simultaneously) than to either of the targets presented alone. This difference in latency is termed the redundancy gain (RG). Chromatic targets may be accompanied with luminance changes at their onset and offset. We have used a dynamic random luminance modulation technique to mask out luminance components of chromatic signals. Here we report on the presence of a significant RG for visual targets defined by their combined luminance and chromatic components as well as their chromatic content in isolation. Reaction times were measured to the onset of three classes of stimuli, namely, Long- and Short-wavelength cone sensitive (L- and S-cone) targets matched for saliency as well as luminance-defined targets. Analysis of the cumulative distributions of reaction time data showed that a neural coactivation model could fit the experimental data for chromatic targets only. When a luminance component is present, the reaction time data can be explained by a probability summation account also known as the race model.

Keywords

Redundant target effect Neural coactivation Probability summation 

References

  1. Barbur JL (2004) ‘Double-blindsight’ revealed through the processing of colour and luminance contrast defined motion signals. Prog Brain Res 144:243–259PubMedCrossRefGoogle Scholar
  2. Birch J, Barbur JL, Harlow AJ (1992) New method based on random luminance masking for measuring isochromatic zones using high resolution colour displays. Ophthalmic Physiol Opt 12(2):133–136PubMedCrossRefGoogle Scholar
  3. Corballis MC (1998) Interhemispheric neural summation in the absence of the corpus collosum. Brain 121(9):1795–1807PubMedCrossRefGoogle Scholar
  4. Corballis MC (2002) Hemispheric interactions in simple reaction time. Neuropsychologia 40:423–434PubMedCrossRefGoogle Scholar
  5. Corballis MC, Hamm JP, Barnett KJ, Corballis PM (2002) Paradoxical interhemispheric summation in the split brain. J Neurosci 14(8):1151–1157Google Scholar
  6. Desimone R, Moran J, Schein SJ, Mishkin M (1993) A role for the corpus callosum in visual area V4 of the macaque. Vis Neurosci 10(1):159–171PubMedGoogle Scholar
  7. Forster B, Cavina-Pratesi C, Aglioti SM, Berlucchi G (2002) Redundant target effect and the intersensory facilitation from visual-tactile interactions in simple reaction time. Exp Brain Res 143:480–487PubMedCrossRefGoogle Scholar
  8. Giray M, Ulrich R (1993) Motor coactivation revealed by response force in divided and focused attention. J Exp Psychol Hum Percept Perform 19:1278–1291PubMedCrossRefGoogle Scholar
  9. Hubel DH, Livingstone MS (1987) Segregation of form, colour & stereopsis in primate area 18. J Neurosci 7:3378–3415PubMedGoogle Scholar
  10. Hughes HC, Reuter-Lorenz PA, Fendrich R, Gazzaniga MS (1992) Bi-directional control of saccadic eye movements by the disconnected cerebral hemispheres. Exp Brain Res 91:335–339PubMedCrossRefGoogle Scholar
  11. Hughes HC, Reuter-Lorenz PA, Nozawa G, Fendrich R (1994) Visual-auditory interactions in sensorimotor processing: saccades versus manual responses. J Exp Psycol Hum Percept Perform 20:131–153CrossRefGoogle Scholar
  12. Iacoboni M, Ptito A, Weekes NY, Zaidel E (2000) Parallel visuomotor processing in the split brain: cortico-sub cortical interactions. Brain 123:759–769PubMedCrossRefGoogle Scholar
  13. Marrocco RT, Li RH (1977) Monkey superior colliculus: properties of single cells and their afferent inputs. J Neurophysiol 40(4):844–860PubMedGoogle Scholar
  14. Miller J (1982) Divided attention: evidence for coactivation with redundant signals. Cognit Psychol 14:247–279PubMedCrossRefGoogle Scholar
  15. Miller J, Ulrich R (2003) Simple reaction time and statistical facilitation: a parallel grains model. Cognit Psychol 46:101–151PubMedCrossRefGoogle Scholar
  16. Miniussi C, Girelli M, Marzi CA (1998) Neural site of the redundant target effect: electrophysiological evidence. J Cogn Neurosci 10(2):216–230PubMedCrossRefGoogle Scholar
  17. Mordkoff JT, Yantis S (1991) An interactive race model of divided attention. J Exp Psychol Hum Percept Perform 17(2):520–538PubMedCrossRefGoogle Scholar
  18. Olavarria JF, Abel PL (1996) The distribution of callosal connections correlates with the pattern of cytochrome oxidase stripes in visual area V2 of macaque monkeys. Cereb Cortex 6:631–639PubMedCrossRefGoogle Scholar
  19. Raab D (1962) Statistical facilitation in simple reaction time. Trans N Y Acad Sci 43:574–590Google Scholar
  20. Regan BC, Reffin JP, Mollwn JD (1994) Luminance noise and the rapid determination of disccrimination ellipses in colour deficiency. Vision Res 34:1279–1299PubMedCrossRefGoogle Scholar
  21. Reuter-Lorenz PA, Gazzaniga MS, Nozawa G, Hughes HC (1995) Fate of neglected targets: a chronometric analysis of redundant target effect in the bisected brain. J Exp Psychol Hum Percept Perform 21(2):211–230PubMedCrossRefGoogle Scholar
  22. Roser M, Corballis MC (2002) Interhemispheric neural summation in the split-brain with symmetrical and asymmetrical displays. Neuropsychologia 40(8):1300–1312PubMedCrossRefGoogle Scholar
  23. Roser M, Corballis MC (2003) Interhemispheric neural summation in the split-brain: effects of stimulus colour and task. Neuropsychologia 41:830–846PubMedCrossRefGoogle Scholar
  24. Savazzi S, Marzi CA (2002) Speeding up reaction time with invisible stimuli. Curr Biol 12(5):403–407PubMedCrossRefGoogle Scholar
  25. Savazzi S, Marzi CA (2004) The superior colliculus subserves interhemispheric neural summation in both normals and patients with a total section or agenesis of the corpus collosum. Neuropsychologia 42:1608–1618PubMedCrossRefGoogle Scholar
  26. Sincich LC, Horton JC (2005) The circuitry of V1 and V2: integration of color, form and motion. Annu Rev Neurosci 28:303–326PubMedCrossRefGoogle Scholar
  27. Stein BE (1998) Neural mechanics for synthesizing sensory information and producing adaptive behaviours. Exp Brain Res 123:124–135PubMedCrossRefGoogle Scholar
  28. Turatto M, Mazza V, Savazzi S, Marzi CA (2004) The role of the magnocellular and parvocellular systems in the redundant target effect. Exp Brain Res 158:141–150PubMedCrossRefGoogle Scholar
  29. Ulrich R, Miller J, Schröter H (2007) Testing the race model inequality: an algorithm and computer programs. Behav Res Methods 39(2):291–302PubMedGoogle Scholar
  30. Xiao Y, Wang Y, Felleman DJ (2003) A spatially organized representation of colour in macaque cortical area V2. Nature 421:535–539PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Vision Research Laboratories, School of PsychologyUniversity of AberdeenAberdeenUK

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